Many ocular procedures involve the insertion of materials into the eye, including fluids, tissues, cells and grafts. During such procedures, one key requirement is the insertion of the various materials through as small an incision as possible to minimize trauma to the eye. Further, due to the delicate nature of many of the materials that are inserted, it is important that the devices and techniques adequately protect the materials during manipulation and insertion. In addition, in light of the need for minimal manipulation of the device within the eye to prevent trauma to the eye, it is important that the device and technique enables precise and controlled insertion at a desired target location within the eye so as to minimize the need for post-insertion repositioning of the material inserted.
Endothelial keratoplasty (EK) is one type of procedure that involves the insertion of tissue into the eye. In particular, EK involves selectively replacing the diseased layer of the cornea and leaving healthy areas intact. During the EK procedure, the diseased inner cell layer of the cornea is removed, and healthy donor tissue is implanted through a small incision. One common method that surgeons have used for inserting tissues within the eye involves the use of forceps to grasp and fold/roll the delicate tissue, followed by inserting the forceps with the grasped tissue into the eye. However, this technique and device cannot be used in a subretinal space and could cause significant trauma to the very delicate retina tissue.
A variety of devices and techniques have been developed that somewhat reduce such eye trauma and tissue damage during insertion of materials into the eye.
For example, U.S. Patent Application Publication No. 2013/0085567 to Tan et al. describes a device and technique that aids in the manipulation of the thin DM/endothelial complex, so as to greatly simplify the donor handling, and AC manipulation stages, of DMEK surgery. The device houses a donor tissue in a coiled configuration within a chamber for transplantation into the eye. The donor tissue is then placed at a desired location within the eye by grasping the donor tissue with forceps which are inserted through a second incision in the eye and pulling the donor tissue out of the chamber into the eye.
U.S. Pat. No. 8,029,515 to Shiuey describes a device and technique for delivering a corneal implant, particularly through a corneal incision that is substantially less than the width of the implant such that the implant is placed within or between any of the layers of the cornea including the epithelium, Bowman's membrane, stroma, Descemet's membrane, and endothelium. The device includes a hollow member that constrains the corneal implant, and an implant mover or axial pusher that is used to engage and push the implant through and out of the hollow member into the corneal pocket.
Thus, while devices and techniques have been developed that somewhat reduce such eye trauma and tissue damage during insertion of materials into the eye, further improvements are still needed to address retina damage issue and placing implant into very limited in space-subretinal compartment. In addition, there is a need for devices and techniques that provide for more precise and controlled delivery of the tissues into the eye.